1. Field of the Invention
This invention relates generally to electronic controls for a heating and air conditioning system and, more particularly, to a control for limiting the amount of overshoot and undershoot in a space conditioning system.
2. Prior Art
In order to keep the temperature within a space to be conditioned at a specified setpoint, a thermostatic control is used to operate the heating and air conditioning system when a temperature sensor indicates a specified difference from a setpoint or desired temperature. However, during the operation of the heating and air conditioning system the actual temperature of space overshoots the desired temperature because of the temperature sensor time constant or lag, and because of the latent heat/cool in the space conditioning system has not yet been transferred to the space when the system is switched off.
Thus, there is a clear need for a control for a space conditioning system that will compensate for the sensor lag and system latent heat during the operation of the space conditioning system to offset the difference between the desired temperature in a space and the actual temperature the space attains after the conditioning system turns off.